48.

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astore

store object reference in local variable

Jasmin Syntax

     astore <varnum> or     wide     astore <varnum> 

In the first form, <varnum> is an unsigned integer in the range 0 to 0xFF. In the second (wide) form, <varnum> is an unsigned integer in the range 0 to 0xFFFF.

Stack

Before	After
objectref	...
...

Description

Pops objectref (a reference to an object or array) off the stack and stores it in local variable <varnum>. The astore instruction takes a single parameter, <varnum>, an unsigned integer which indicates which local variable is used. <varnum> must be a valid local variable number in the current frame.

Example

 aload 1    ; Push object reference in local variable 1 onto stack astore 3 ; and store it in local variable 3 

Bytecode

For local variable numbers in the range 0-255, use:

Type	Description
u1	astore opcode = 0x3A (58)
u1	<varnum>

There is also a wide format for this instruction, which supports access to all local variables from 0 to 65535:

Type	Description
u1	wide opcode = 0xC4 (196)
u1	astore opcode = 0x3A (58)
u2	<varnum>

See Also

lstore, istore, dstore, fstore, wide

Notes

astore can also be used to store a returnAddress in a local variable. See the jsr instruction for more details.

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Java Virtual Machine, by Jon Meyer and Troy Downing, O'Reilly Associates